High performance lamps, such as HiPer Vision lamps by Philips, are interesting in the automotive industry for various reasons, among which because they have a useful life that is of the same order as that of a vehicle equipped with such lamps. In other words, it is seldom necessary to replace these lamps.
To prevent deterioration of high performance lamps, they are usually assembled to the lamp socket through a clickable plastic element.
A lighting device assembly 1 of the prior art, as depicted on FIG. 5, comprises a lamp 2 and a lamp socket 3. The lamp socket contains the necessary electric connections in order to supply power to the lamp 2. The lamp 2 has a lamp bulb 21 and a lamp base 22 which cooperates with the lamp socket 3 for power supply and positioning, for instance with current conducting elements (not shown) lodged in corresponding housings provided on the lamp socket 3. In order to prevent the lamp 2 from being dislodged from the lamp socket 3, the lamp socket 3 is equipped with catch element 31, which comprises a plurality of catch flanges 32. The catch flanges 32 extend perpendicularly to the lamp socket plane. They may be regularly arranged along a circle. The catch flanges comprise a flange head 33 and a leg 34. The flange head 33 has a bevelled guiding surface 35 which ends at a shoulder 36. When a lamp 2 is pushed in the lamp socket, the catch flanges 32 are pushed outwardly along their bevelled guiding surface 33 until the shoulder 36 engages with the base 22 of the lamp 2. Thus, the lamp 2 is assembled to the lamp socket 3 with a clickable catch element 31. The lamp socket may be made of a heat resistant plastic material, in order to prevent damage to the lamp 2.
However, in various appliances such as daytime running appliances where the catch element 31, and more particularly the catch flanges 32, undergoes prolonged mechanical stress under long term exposure to heat, the catch element 31 may suffer permanent deformation. Such observations have been made after a long time span, for instance from a few weeks to a few months. This may result in the lamp 2 becoming loose in the lamp socket 3, which is undesirable for various reasons such as security or obligation to remove the lamp assembly and replace it although the lamp has not reached its useful life yet.